Dense core vesicles, also known as secretory granules or dense granules, are membrane-bound organelles found within cells that play a crucial role in the regulated secretion of various bioactive molecules. These vesicles are unique in structure and composition compared to other vesicles in the cell.
Dense core vesicles are typically larger in size and have a dense, electron-dense core surrounded by a single lipid bilayer membrane. The dense core is made up of various proteins, peptides, hormones, and neurotransmitters that are synthesized and packaged within the cell's endoplasmic reticulum and Golgi apparatus.
These vesicles are primarily found in specialized secretory cells, such as neurons, endocrine cells, and certain immune cells. They are responsible for storing and releasing specific molecules in response to various stimuli or signals.
When the cell receives a signal, dense core vesicles undergo exocytosis, a process where the vesicle fuses with the plasma membrane, releasing its content into the extracellular space. This regulated secretion allows for precise control over the release of bioactive molecules, contributing to various physiological processes, including neurotransmission, hormone regulation, immune responses, and cell-to-cell communication.
Dysfunction or disruption of dense core vesicles can lead to various diseases and disorders, including neurological disorders, endocrine disorders, and immune system dysregulation. Hence, understanding the structure and function of dense core vesicles is crucial for exploring the underlying mechanisms of cellular communication and developing therapeutic interventions.
